Leaf burner



Mmih 3, 1970 D. H. mow 3,498,240

LEAF BURNER Filed June 10, 1968 INVENTOR.

ATW/VEW United States Patent 3,498,240 LEAF BURNER David H. Trott, Cincinnati, Ohio, assignors, by mesne assignments, to Burns Investment Corp., Cincinnati, Ohio, a corporation of Ohio Filed June 10, 1968, Ser. No. 735,839 Int. Cl. F23g 5/00; F23b 1/38 US. Cl. 11018 12 Claims ABSTRACT OF THE DISCLOSURE This invention relates to a burner for the purpose of disposing of combustible wastes, such as rubbish, trash and tree leaves and to a method of burning such combustibles in a substantially closed container.

Many homeowners do not have any access whatever to trash pickup service. Many more do not have adequate trash can capacity to accommodate all the trash they accumulate between pickups. This explains why a great many such homeowners follow the practice of regular burning of waste materials all year round. The enabling facilities available to such homeowners are unsophisticated, however, and do little to minimize this chore.

In addition to normal trash generated by daily living, most homeowners face a seasonal problem every fall in disposing of fallen tree leaves. In some communities the loose burning of leaves is not permitted and the homeowners must rake his leaves to the street and at regular intervals these leaves are picked up by the city. This is reasonably satisfactory, although the removal of the leaves is an expense to the city, and, where leaves are not picked up contemporaneously with the raking of them onto the street, the wind may very well simply distribute the leaves piled on the street to the yards of the adjoining properties.

In other communities the leaves are burned in the street or yard by the homeowner. Such open burning presents fire hazards, and the clouds of smoke generated by the leaf burning certainly are not compatible with the air pollution problem which plague so many communities.

In some locations neither is possible, that is, the city will not pick up the leaves and the homeowner has no convenient place for burning them. In such a situation, the disposal of the leaves is at best inconvenient and/or expensive.

An objective of the present invention has been to effect the disposal of combustible waste as follows:

A container, or burning chamber, is filled with waste material. The top layer of said material then is ignited. As soon as a self-sustaining flame is achieved, the cham her is closed and forced air is fed into the inlet port located on the upper side of the chamber. The forced air may be generated by a blower attached to the device, or taken from another source. The combustion process is accelerated greatly by said air and, as it proceeds, consumption of the uppermost material continually exposes the adjacent underlying material to the flames. As a result, the fire bed progresses gradually downward in the burning chamber, until all combustible material has been burned. Combusted gases escape through the exhaust chamber. The egress preferably is covered by a foraminous screen or basket which serves as a strainer to aid in retaining flaming materials. From time to time, in the latter stages of the burning, completion of the process may be expedited by inserting a rod into the chamber, through a small porthole in the top provided for this purpose, and used to agitate the remaining contents.

An objective of the present invention has been to provide a means of burning leaves or other waste which is both speedy and safe, with a minimum of hazard from flying embers. Open burning is unsatisfactory in this respect, and those incinerators consisting basically of a perforated container are extremely slow. The present invention, being closed except for a relatively small exhaust port, permits the escape of little or no burning material. The use of forced air, however, greatly speeds up the burning process. Furthermore, this air is introduced in such a way to utilize the well-known principles underlying the cyclone furnace, taking advantage of centrifugal force to restrain still solid materials from reaching the exhaust port.

Another objective of the present invention has been to make the burning of leaves and waste material as smokefree as possible. This is accomplished by the novel concept of burning from the top down, rather than from the bottom up, which is the normal procedure.

Another objective of the present invention has been to provide the average homeowner with a means of burning leaves and other Waste which is not only speedy and efficient, but also inexpensive and compact. These objectives, too, are served by the novel principle of burning from the top down. All of the special physical features of the invention are concentrated in the top portion of the device, with the balance of the hardware serving simply as a chamber to contain the material while it is being consumed. Thus, it is possible to manufacture this top portion only, in the form of a special lid or cap, which the homeowner simply places on a stadnard ZO-gallon trash can when he Wishes to burn waste material. Since such a unit can be about the size of a drum or hat box, storage would present no problem.

With respect to said special lid, another objective of the invention has been to provide a satisfactory operational fit between lid and can during operation. This is accomplished by flanges depending from the lid which present an annular groove which receives the upper edge of the trash can.

Another objective of the invention has been to regulate the flow of air so that a reduced flow of air can be employed initially in order to accelerate the combustion of the products within the trash can without blowing out the flame. After combustion is widespread within the can, the flow of air is turned to maximum to effect the rapid burning of the combustibles. Said regulator also may be employed to reduce the vigor of the combustion during manual agitation of the burning material.

It has been another objective of the invention to provide the lid with a small opening through which a rod can pass to agitate the contents within the trash burner when desirable.

It has been another objective of the invention to provide a hinged cap which permits the trash burner to be loaded for burning without requiring the removal of the lid.

These and other objectives of the present invention Will become more readily apparent from the following detailed description taken in conjunction with the accompanying drawing which is a perspective view partly in section showing the invention.

Referring to the drawing, the trash burner indicated at 10 includes a 20-gallon trash can 11 and a lid 12 formed in accordance with the present invention. It should be understood, of course, that there is no requirement that the lid 12 of the invention be associated specifically with a 20-gallon trash can. That size is preferred because of the extensive use of that size of can throughout the United States. Said lid could be designed to fit a larger trash can, or some other container such as an oil drum.

The lid has a pillbox-shaped housing 13 at its upper portion, the pillbox shape being formed by a cylindrical ring 14 and a cap 15 which is hinged to the ring 14. The cap can be rigidlyfixed to the ring 14 with the can 11 being loaded by removal of the entire lid.

The lower edge of the ring 14 is Welded to a skirt 16 formed by two spaced depending flanges 17 and 18 which form between them an annular groove having an inside diameter of 16.5 inches and an outside diameter of 19.5 inches into which the upper rim 19 of the trash can (having a diameter of approximately 17.5 inches) projects to seat the lid on the trash can.

The ring 14 has an inlet opening 22 to which a tangentially directed tube 23 is secured. A blower 24 is mounted on the tube 23 to direct air into the trash burner. At the low pressure or inlet side of the blower, a regulator 27, for varying the size of the inlet opening, is rotatably applied so as to permit the regulation of the air discharged into the trash burner.

Alternatively, and not shown, the inlet tube 23 can be connected to a standard vacuum cleaner hose which is connected to the high pressure end of a vacuum cleaner. Through this adaptation of the invention, the homeowner can be offered the invention in a form which would minimize his investment by eliminating the need for a blower.

The cap 15 has a central exhaust opening 26 which is about one-fifth the diameter of the lid itself. A foraminous strainer 28, which can be removable or fixed to the cap, is inserted in the opening 26 and prevents the exit of large pieces of burning material. The strainer should be of stainless steel or another material which is resistant to high heat.

A small hole 30 which is coverable by a pivoted flap 31 is formed in the cap 15 near the outer edge. The hole 30 is adapted to receive an elongated stirring implement as, for example, a piece of rod or the like with which the contents within the trash burner can be stirred. This stirring action is useful in the later stages of combustion wherein the remaining combustible material may tend to compact itself and thus slow completion of the burning process.

The operation of the invention is as follows:

Leaves or other trash are placed in the can 11 when the lid 12 is removed or, alternatively, when the lid 12 is in position and its cap 15 is pivoted to open position as shown in broken line in the figure. With the cap raised, the combustibles are ignited and then the cap is closed.

Once the combustibles are ignited, the blower is energized and preferably has its intake partly blocked by the regulator 27. The gentle breeze from the blower fans the flame until it spreads throughout the top of the combustibles, this requiring a very few seconds of time. Thereafter, the inlet to the blower is opened fully and the blast of air introduced tangentially swirls around the top of the combustibles to effect their rapid burning. The combusting gases exhaust through the strainer in a substantially completely oxidized state. That is to say, there is practically no smoke or particulate material which passes through the strainer 28 during the operation. Hence, the burning is quite clean and should not be ofiensive to ones neighbors.

As burning progresses and the top two-thirds of the combustibles are burned away, the operator might find it advantageous to open the flap 31 and to stick a rod through the opening 30 to stir the combustibles remaining in the bottom of the trash can to speed their burning. The burning follows generally the path of the arrows shown in the drawing wherein the air flows tangentially around the top of the cap and then down into the combustibles and upwardly out through the discharge opening or exhaust opening 26.

Burning of large quantities of leaves or other material may be expedited by the use of more than one trash can. Leaves are gathered and packed in one trash can, the lid of the present invention applied, and the leaves are ignited. As the leaves in this trash can are being burned, another trash can can be filled. Then, after combustion in the first can is completed, the lid can be transferred to the other filled can and the burning process repeated.

In the alternative embodiment of the invention as a complete unit, a clean-out port could be provided at the bottom to facilitate periodic ash removal (not shown).

The invention also could be fitted with an integral agitation apparatus, installed internally but operated by external means (not shown).

What is claimed is:

1. A burner comprising:

a housing, said housing being generally cylindrical,

said housing having -a normally closed top and having an inlet opening and an exhaust opening, said housing being open at the bottom,

said inlet being located at the top of the side wall of said housing, and directed tangentially into it, said exhaust opening being located in the center of the top of said housing,

means for connecting a source of forced air to said inlet opening,

means for mounting said housing on top of an underlying chamber to close same.

2. A burner according to claim 1 further comprising an underlying combustion chamber, said housing fixed to said chamber, said chamber being cylindrical in form in its upper portion, said chamber being open at the top, said chamber being normally closed at the bottom.

3. A burner according to claim 1 wherein said mounting means comprises a pair of spaced concentric circular flanges depending from said housing and forming between them an annular groove to removably receive the top of an underlying container.

4. A burner according to claim 3 in which said groove has an inside diameter of approximately 16.5 inches and an outside diameter of approximately 19.5 inches.

5. A burner according to claim 1 further comprising a foraminous strainer covering said exhaust outlet.

6. A burner according to claim 1 in which said top is hinged at one edge to said housing, permitting said top to be raised to provide access to the underlying burner chamber for the purpose of filling it with combustible material.

7. A burner according to claim 1 in which said housing includes a stirring opening spaced from said exhaust and inlet openings, said opening having a covering flap fastened to said housing and adapted selectively to overlie said stirring opening.

8. A burner according to claim 1 further comprising a blower mounted on said housing and connected to said housing inlet, said blower thus being a component of said housing, and constituting the source of said forced air.

9. A burner according to claim 8, further comprising a regulator governing the supply of air to said blower to regulate the rate of supply of said forced air to said housing.

10. A burner cap comprising:

a circular ring having an inlet opening therein,

a circular plate secured to the upper edge of said ring,

a pair of depending concentric spaced flanges secured to the lower edge of said ring and forming an annular groove adapted to receive the top of a trash can,

said lid having an exhaust opening in the center thereof, and

a foraminous strainer in said exhaust opening.

11. A burner comprising: introducing forced air tangentially only to the top layer a container open at the top and defining a combustion of said material, thus establishing a circular pattern of chamber for burning combustibles, air movement within the chamber, progressively burning a housing, the combustible material from the top downward, permitting escapement of combusted gases centrally and above said material.

means removably mounting said housing on the top of said container to close the same, said housing having an air inlet opening exiting directly into the upper end of said container when References Cited sa1d housing 1s mounted on said container, and hav- UNITED STATES PATENTS mg an exhaust opening, and 10 means for connecting a blower to said inlet opening, 2 707 444 5 1955 Van Loon 110. 28 whereby forced air is introduced to the top layer of 2 936 724 5 /19 0 i h 11 1g said combustibles to burn the combustibles prog- 3 23 6 11 /19 6 01 1 110 3 ressively from the p downbl 3,202,11-8 8/1965 Baldine 110-18 12. The method of burning combusti es comprising 1r the steps of depositing a batch of said material in a FOREIGN PATENTS generally cylindrical chamber, igniting the top layer of 1,031,401 3/1953 France.

said material, closing said chamber except for inlet and exhaust openings located at the top of said chamber, KENNETH W. SPRAGUE, 'y EXamlIlef 

